Nearly all my remodeling jobs involve some kind of tile, so I'm constantly doing tile layout. Before I had a layout laser, I used a large folding square to create 90-degree layouts, or I drew a 3-4-5 triangle on the floor. With a laser I can skip that cumbersome step and set tile to the laser's beams. It's far more convenient than working to snapped lines, which can be obscured by the application of thinset.

Last fall I tested Bosch's new GTL3. Because it's taller than other tile lasers, its beams are better at clearing obstructions. Also, while most tile lasers have a pair of lines set 90 degrees apart, the GTL3 has three lines, so it can project both 90-degree and 45-degree angles. The third beam comes in handy when you're installing a diagonal field within rectangular borders.

Bosch's laser is controlled by a single button and can be set to project square-only or square and diagonal lines. To conserve the batteries it automatically shuts down after 30 minutes. It's sold in a soft case small enough to fit under the seat of a truck.

Performance
The GTL3 has a small footprint, so it works well in tight quarters. According to Bosch, the laser has a working range of 65 feet. In practice, though, its range is less, because the beams — which are crisp and bright near the tool — widen and fade with distance.

In brightly lit areas the beam will be visible on the floor 6 or 8 feet out; in dim lighting it may be visible to 10 or 15 feet. Beyond that distance the beam cannot be seen on horizontal surfaces — though it can be seen on vertical ones, such as on the included laser target or on the face of a tape or trowel. Viewing the beam on a vertical surface is fine for marking or measuring layout, but it's not as useful as being able to see the beam go all the way across the floor.

The simulated beams in these photos from the manufacturer (top) show how the laser projects layout onto floors and walls. The actual beams are far less bright, as can be seen in the photo above, which was taken without the use of a flash.

I have successfully used this laser to measure out to about 20 feet in a dimly lit room by holding a folding rule on edge so that the beam hit it. At that distance the beam is approximately 1/8 inch wide, which is twice as wide as it is directly in front of the tool. At 50 feet out, the beam is about 7/16 inch wide. Personally, I would not choose to use this laser for distances beyond 25 feet.

Leveling Plate
Magnets in the base of the laser allow it to be attached to a metal leveling plate sold with the tool. The plate stabilizes the laser and raises it above the thinset, keeping it clean. By screwing the plate to the wall and attaching the laser, you can project layout for wall tile — a feature I deemed less impressive once I realized the device cannot self-level. Projecting layout onto a vertical surface means aligning the beam with a level line created with some other tool.

The Bottom Line
The Bosch tile laser is great for what it is: a small, relatively inexpensive tool for doing square and diagonal layout. I wouldn't use it on a large commercial project, but it's extremely useful in the bathrooms and small kitchens that make up the bulk of my work.